Microcontroller based automation system using industry standard SCADA

SCADA (Supervisory Control and Data Acquisition) is a type of industrial control system. In typical industrial automation applications, PLCs are used to communicate between the plant and SCADA. In this paper we are using a low cost microcontroller to understand the various control techniques and capabilities of SCADA and implement them in real time. A simple temperature control scheme is developed using ATMEGA2560 microcontroller and industry standard SCADA software Vijeo Citect v7.2. We make use of MODBUS ASCII protocol which is an industry standard communication protocol to set up a temperature control system which collects real time temperature data, processes the data and performs the desired control action. Major contribution of the paper is in developing MODBUS library for communication between microcontroller and SCADA and implementing control algorithms such as ON/OFF and proportional controller on data obtained in real time. Thus this paper presents a low cost automation scheme which can be easily extended for more complicated control schemes including wireless control. The project has been developed as first step towards a project on pipeline leakage detection scheme using wireless sensor nodes.